Global.Intl.NumberFormat

// Set up to pad first 3 integer digits with zeros if needed.
const formatter = new Intl.NumberFormat(Ti.Locale.currentLocale, {
    minimumIntegerDigits: 3,
    useGrouping: false
});

// Logs: 000
console.log(formatter.format(0));

// Logs: 001
console.log(formatter.format(1));

// Logs: 001.23
console.log(formatter.format(1.23));

// Logs: 12345
console.log(formatter.format(12345));

// Round up to 3 significant digits.
// All trailing non-fractional digits will be zero.
const formatter = new Intl.NumberFormat(Ti.Locale.currentLocale, {
    maximumSignificantDigits: 3,
    useGrouping: false
});

// Logs: 12300
console.log(formatter.format(12345.6));

// Logs: -12300
console.log(formatter.format(-12345.6));

// Logs: 1.23
console.log(formatter.format(1.23456));

// Set up currency style format options.
const options = {
    style: 'currency',
    maximumFractionDigits: 2,
    minimumFractionDigits: 2,
    useGrouping: true
};

// Format in dollars in USA. Logs: $1,000.00
// Note that the "currency" option is required.
let formatter = Intl.NumberFormat('en-US', Object.assign({ currency: 'USD' }, options));
console.log(formatter.format(1000));

// Format in euros in USA. Logs: €1,000.00
formatter = Intl.NumberFormat('en-US', Object.assign({ currency: 'EUR' }, options));
console.log(formatter.format(1000));

// Format in euros in Germany. Logs: 1.000,00 €
formatter = Intl.NumberFormat('de-DE', Object.assign({ currency: 'EUR' }, options));
console.log(formatter.format(1000));

// Format in dollars in Germany. Logs: 1.000,00 $
formatter = Intl.NumberFormat('de-DE', Object.assign({ currency: 'USD' }, options));
console.log(formatter.format(1000));

// Set up percentage style numeric formatting.
const formatter = new Intl.NumberFormat(Ti.Locale.currentLocale, {
    style: 'percent',
    maximumFractionDigits: 1,
    minimumFractionDigits: 1,
    useGrouping: false
});

// Logs: 25.0%
console.log(formatter.format(0.25));

// Logs: 100.0%
console.log(formatter.format(1.0));

// Logs: 1234.5%
console.log(formatter.format(12.345));

// Logs: 1234.6%
// Since value exceeds "maximumFractionDigits" of 1, it is rounded.
console.log(formatter.format(12.3456));

// Logs: 1.235E5
// Decimal point will be a period, comma, or space depending on the locale.
const formatter = new Intl.NumberFormat(Ti.Locale.currentLocale, { notation: 'scientific' });
console.log(formatter.format(123456.7));